Half-height magnetic disk device having a lead wire retaining groove in the actuator arm

ABSTRACT

A magnetic disc device of half-height type comprising: a base; four magnetic discs disposed one above the other on the base; five head arms rotatable about a pivot for seeking motion on both surfaces of each magnetic disc; eight magnetic heads each attached to an end of the head arm through springs facing a surface of each disc; a rotational drive unit for swinging the head arms; a main printed circuit board disposed on a rear side of the base; and, a cover which covers an upper surface of the base.

This application is a continuation of application Ser. No. 08/068,610,filed May 27, 1993, (now abandoned) which was a continuation of Ser. No.07/748,504, filed Aug. 22, 1991 (now abandoned) which in turn was adivision of Ser. No. 07/463,838, filed Jan. 11, 1990, (now U.S. Pat. No.5,060,100) which in turn was a continuation of Ser. No. 058,148, filedJun. 4,1987, (now abandoned).

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates to a magnetic disc device used as a memorymeans for mini-computers or micro-computers.

Conventionally, a Winchester type magnetic disc device using hard discs3.5 inches in diameter has been used as a memory means formini-computers or micro-computers. Such a magnetic disc devices musthave a high memory density without any enlargement of the size thereof,to ensure that it is compatible with other conventional devices.Therefore, an improved magnetic disc device has been developed, whichhas a high memory density enriched by increasing the number of magneticdiscs.

(2) Description of the Related Art

A conventional magnetic head of a known magnetic disc device isillustrated in FIGS. 13a and 13b. A magnetic head 5 includes coil leadwires 5a which are drawn upward in the direction opposite to a slidersurface 5b. With this structure, the lead wires 5a may sometimes comeinto contact with a disc surface disposed above the magnetic head oranother magnetic head disposed above and opposing this magnetic head 5which will cause a short circuit or an instability of the head when inoperation the head is separated from the disc surface and floatingthereon.

Also, the conventional magnetic disc device includes a head actuatorhaving a pivot 6f, as shown in FIG. 14. The pivot 6f has a plurality ofhead arms 6e which are secured to an outer sleeve 10. The outer sleeve10 is installed on a stationary shaft 12 through two roller bearings 11and 11'. The shaft 12 is disposed on a seat 12a for vertical positioningwhen secured to the base 1 through a screw. The diameter of the seat 12ais approximately the same as that of the outer sleeve 10. Therefore, thespace corresponding to the height H of the seat 12a is wasted, thuscausing an unnecessary enlarging of the case of the magnetic discdevice.

A magnetic device has a record medium on which information data isrecorded and a magnetic head for reading the information from thatmedium. The magnetic head is disposed in such a manner that it faces therecording area of the record medium, to transmit information databetween the record medium and a read/write device.

When a magnetic disc is used as the magnetic medium, the head isattached to a head arm which carries the head and positions it at adesired track in the recording area of the magnetic disc. Therefore, inorder to achieve an accurate positioning of the head at a high speed, itis necessary to reduce the weight of the head construction, includingthe head arm, to minimize the inertial force thereof.

A known magnetic head structure is illustrated in FIG. 12. A head 33 issupported at an end of a gimbal 32 which is secured to a head arm 31.Information data is transmitted between the head and a read/write devicethrough a lead wire 34. A springy clip 35 made of plastic is attached tothe head arm 31 to hold the lead wire 34 between the head arm 31 and theclip 35 along the head arm side edge.

With the above-mentioned magnetic head structure of the prior art, thehead arm 31 becomes heavy, since the clip 35 is used for holding thelead wire 34, thus opposing the requirement for reducing the weight ofthe head arm structure. Also, the gap between the discs must be wideenough to accommodate the clips 35 therebetween, thus preventing areduction of the height of the magnetic device.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide a magneticdisc device in which the problem of a short circuit of the lead wires oran instability of the magnetic head when in operation separated from thedisc surface and floating thereon is eliminated.

Another object of the present invention is to provide a magnetic discdevice which eliminates unnecessary dead space due to the pivot seat ofthe head actuator, thus realizing a more compact device.

A further object of the present invention is to provide a magnetic discdevice having a light weight head structure.

The present invention especially realizes a half-height type magneticdisc device having a swing type actuator and four magnetic discs housedtherein.

The height dimension of the magnetic disc device is commerciallystandardized and a full-height type magnetic disc device is marketed.Also, a half-height type magnetic disc device has been developed torealize a small size magnetic disc device which is compatible with thefull-height type magnetic disc device. This type is advantageous fromthe standpoint of space saving since the height is one half that of thefull-height type magnetic disc device.

On the other hand, when the capacity of the magnetic disc device is tobe increased using an ordinary interface circuit, it is desirable todouble the number of the discs, from the standpoint of easy installationof a new magnetic disc device having an increased capacity in place ofan old device. It is relatively easy to exchange an old device with anew one and/or simultaneously use a new device with an old one throughan ordinary interface circuit. Therefore, a two-disc magnetic discdevice was developed as an improvement on a one-disc magnetic discdevice. Subsequently, a magnetic disc device comprising four discs hasbeen developed as an improvement on the two-disc device.

The present invention makes it possible to house four discs in ahalf-height type magnetic disc device, which could not be realized bythe known devices, since four discs could not previously be stacked inthe shortened half-height type device housing of the known structures.

In accordance with the present invention, there is provided ahalf-height type magnetic disc device having a base, four magnetic discsdisposed one above the other on the base, five head arms rotatable abouta pivot for a seeking motion on both surfaces of each disc, eightmagnetic heads each attached to an end of the head arm facing a surfaceof each disc, rotational drive means for swinging the head arms, a mainprinted circuit board disposed on a rear side of the base, and a coverwhich covers an upper surface of the base.

Preferably, the magnetic head includes a slider and a core disposed at aback side of the slider for winding a coil thereon, a lead wire of thecoil being taken out from an intermediate position of the core along theheight thereof.

The pivot preferably has an outer sleeve to which the five head arms aresecured, a stationary shaft secured on the base and on which the outersleeve is rotatably installed, and a seat on which the shaft issupported on the base, the seat having an inclined periphery and theouter sleeve having a lower inner annular edge inclined to face theinclined periphery of the seat.

Preferably, each of the head arms has a groove formed thereon, the leadwire being fitted and held in the groove.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a magnetic disc device according to the presentinvention, with the cover removed;

FIG. 2 is a vertical sectional view of the magnetic disc deviceaccording to the present invention;

FIG. 3 is a perspective view of a head arm drive means of the magneticdisc device according to the present invention;

FIG. 4 is a partial, exploded view of a head support structure of themagnetic disc device according to the present invention;

FIG. 5 is an exploded view of the magnetic disc device according to thepresent invention;

FIG. 6 is a plan view of a head arm of the magnetic disc deviceaccording to the present invention;

FIG. 7 is a plan view of a head arm of the magnetic disc deviceaccording to the present invention;

FIG. 8(a) is a plan view of another example of a head arm according tothe present invention;

FIG. 8(b) is a sectional view taken along line A--A' of FIG. 8(a);

FIG. 9(a) is a plan view of another embodiment of a head arm of thepresent invention.

FIG. 9(b) is a sectional view taken along line B--B' of FIG. 9(a); and

FIG. 9(c) is a sectional view taken along line C--C' of FIG. 9(a);

FIG. 10(a) is a plan view of an embodiment of a magnetic head of thepresent invention; and

FIG. 10(b) is a front view of the FIG. 10(a) embodiment;

FIG. 11 is a sectional view of a pivot of the magnetic disc deviceaccording to the present invention;

FIG. 12 is a plan view of a known magnetic head arm;

FIG. 13(a) is a plan view of a magnetic head; and

FIG. 13(b) is a front view of the FIG. 13(a) magnetic head; and,

FIG. 14 is a sectional view of a pivot of a known magnetic disc device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 5 is an exploded perspective view of a magnetic disc deviceaccording to the present invention. The magnetic disc device includes ahousing formed by a base 1 and a cover 2, four magnetic discs 4 securedto a spindle 3, eight magnetic heads 5 for magnetic read/writeoperations at the upper and lower surfaces of each magnetic disc 4, anda head actuator 6 for swinging the magnetic heads 5 in the direction ofthe arrow AA' on the magnetic disc surfaces. The head actuator 6includes a drive motor 6a, a capstan 6b, a steel belt 6c, a sector 6d,head arms 6e, and a pivot 6f. Below the base 1 are disposed a spindledrive motor (not shown), a printed circuit board for driving the spindledrive motor (not shown), and a main printed circuit board 7 mounting aread/write circuit for reading data from and writing data on themagnetic discs. Each magnetic head 5 is attached to a head arm 6ethrough a gimbal spring and a load spring 8.

The magnetic disc device illustrated in FIG. 1 is seen from the upperside thereof; with the cover removed, FIG. 2 shows a vertical sectionthereof. The magnetic disc device is of a half-height type having acommercially standardized outer shape dimension. That is, the discdiameter is 96 mm, the longitudinal length a=146±0.5 mm, the laterallength b=101.6±0.5 mm, and the height c=41.3±0.3 mm. A bottom plate 30(FIG. 2) for covering the main printed circuit board 7 is disposed belowthe base 1 and secured thereto together with the main printed circuitboard 7 by screws. The height c is the dimension between the lowestsurface of the bottom plate 30 and the top surface of the cover 2. Thegap d between the adjacent magnetic discs 4 is 4.5 mm, and the thicknesst of each magnetic disc 4 is 1.27 mm. Five head arms 6e are arranged toconduct a seeking motion on both surfaces of the four magnetic discs 4,as shown in FIG. 2. The thickness of the two uppermost and lowermosthead arms is 2.0 mm, and the thickness of the three intermediate headarms is 2.8 mm. The tip of each head arm 6e is thinned to 1.154 mm toattach the load spring 8. The gap between the lower surface of thelowermost magnetic disc 4 and the upper surface of the base 1 is 3.5 mm.Also, as described later, the gap w (FIG. 11) between the lower surfaceof the lowermost head arm 6e at the pivot portion and the upper surfaceof the base 1 is 0.5 mm.

The magnetic discs 4 rotate in the direction of the arrow R (FIG. 1). Abaffle plate 41 is disposed corresponding to each of the four magneticdiscs 4 facing the upper surface thereof. A filter 42 is incorporated ineach baffle plates 41 to remove dust particles from the disc surface.

The magnetic head 5 is connected to a flexible printed circuit board 43(shown by broken line) bonded behind the head arm 6e through a lead wire5a'. A head IC (preamplifier) 44 is mounted on the flexible printedcircuit board 43 behind the head arm 6e. The flexible printed circuitboard 43 is connected to a connector 45 disposed at a corner of thebase 1. The flexible printed circuit board 43 is loose and can be foldedback and forth at the rear end of the head arm 6e to allow free movementwithout impeding the swing motion of the head arm 6e. The connector 45is connected to the main printed circuit board 7 (FIG. 5) disposed underthe base 1.

The head arm 6e has a counter weight portion 46 mounted at the sideopposite the magnetic head attaching end thereof with respect to thepivot 6f. With the provision of the counter weight portion 46, it ispossible to balance the weight of the head arm 6e with respect to thepivot 6f, thus achieving a smooth and stable swing motion of the headarm 6e irrespective of the attitude of the device.

The swing actuator structure of the head arm 6e is illustrated in detailin FIG. 3. The head arm 6e is rotatable about the pivot 6f, as shown bythe arrow Q, and a mushroom-shaped sector 6d is secured to the head arm6e. A capstan 6b is disposed facing and adjacent to a head portion ofthe sector 6d. The capstan 6b is rotatable about a shaft 48, as shown bythe arrow P, a tension spring 47 is attached to a stem portion of thesector 6d. An end of a steel belt 6c is bonded to the tension spring 47.Another steel belt 6c' is secured to the opposite side of the sector 6d.Both steel belts 6c and 6c' are wound around the capstan 6b and securedthereto at the back thereof by a screw. Both steel belts may be formedas one strip. With this structure, the capstan 6b is rotated as shown bythe arrow P to swing the sector 6d through the steel belts 6c, 6c', thusrotating the head arm 6e as shown by the arrow Q about the pivot 6f.Numeral 13 designates a groove for holding the lead cable 5a', asdescribed later in detail.

The structure for supporting the magnetic head 5 is illustrated indetail in FIG. 4. The load spring 8 is made from a leaf spring. A gimbal9 also made from a leaf spring is bonded to an end of the load spring 8by spot welding. A support piece 9a is formed by cutting the inner areaof the gimbal 9. The support piece 9a is bonded to an upper recesssurface 50 of the magnetic head 5. The magnetic head 5 has a core 5d onwhich a coil (not shown) is wound and the coil lead 5a is taken outtherefrom, as described in detail later. The coil lead 5a is covered bya protecting outer tube to form a lead cable 5a' emanating from the endportion of the load spring 8. A root portion 8a of the load spring 8 issecured to the end of the head arm 6e (FIG. 5). As shown in FIGS. 1, 4,5 and 10, coil lead 5a extends from an intermediate portion of asidewall of the head 5 and is connected to lead cable 5a'. Lead cable5a', in turn, extends along the top surface of load spring 8 within theheight of the load spring to a point outside of the magnetic disc andthen is held in groove 13 formed within the height of head arm 6e on thebottom thereof.

A magnetic head coil structure according to the present invention isillustrated in FIGS. 10(a) and 10(b), wherein FIG. 10(a) is a plan viewand FIG. 10(b) is a front view. In the drawings, the magnetic head 5 isformed as a slider having a slider surface 5b and a core 5d on which acoil 5e is wound. Reference 5a designates a coil lead, reference 5cdesignates an opening for forming a gap, and references 5f and 9designate a gap and a gimbal, respectively. The gimbal 9 is bonded tothe magnetic head 5 at the hatched portion thereof.

As can be seen from the drawings, the lead wire 5a of the coil 5e of themagnetic head 5 is taken from the lateral side of the opening 5c. Thatis, the coil lead 5a is taken from the intermediate portion of its core5d along the height thereof instead of the top of the core 5d as in theknown structure of FIG. 13. Thus, the coil lead 5a is connected to thelead wire cable 5a' within the height H₁ shown in FIG. 10b.

The height H₁ of this embodiment can be shortened and the distancebetween the magnetic discs can be reduced without allowing the lead tocome into contact with the disc surface, since the lead wire 5a is takenfrom the lateral side of the opening 5c in parallel with the slidersurface 5b.

The lead wire 5a is disposed along the head arm through the load springand connected to an amplifier attached behind the head arm. Preferably,the lead wire cable 5a' is fitted and held in a groove 10 formed in asurface of the head arm 6e, to reliably hold the cable and avoid contactbetween the cable and the disc surface.

As mentioned above, in accordance with the present invention, it ispossible to reduce the distance between the magnetic discs with a simplestructure without allowing the lead wire to come into contact with themagnetic disc surface, thus realizing a compact arrangement of themagnetic discs which is practically very useful.

A pivot structure of the head arm according to the present invention isillustrated in FIG. 11. In the drawing, numeral 1 designates a base, 6edesignates a head arm, 10 designates an outer sleeve, 11 and 11'designate roller bearings, and 12 designates a stationary shaft.

As shown in the drawing, this embodiment of the pivot structure includesthe outer sleeve 10, which supports a plurality of head arms 6esimultaneously, and the stationary shaft 12 which rotatably supports theouter sleeve 10 thereon through two roller bearings 11 and 11'. Thestationary shaft 12 is placed on a seat 12a having a diameter which isapproximately the same as that of the outer sleeve 10, to ensure theverticality of the shaft which is secured to the base 1 by a screw,similar to the known structure of FIG. 14. A primary feature of thisembodiment resides in the structure wherein the inner peripheral edge ofthe lower end of the outer sleeve 10 is inclined and the outer peripheryof the seat 12a of the shaft 12 is also inclined in a direction facingthe inner inclined lower end of the outer sleeve 10.

With such a structure, the seat 12a is arranged to fit into the inclinedlower inner edge of the outer sleeve 10, thus eliminating theunnecessary dead space corresponding to the height H of the seat asdescribed with reference to FIG. 14 of the known structure. Therefore,it is possible to reduce the height of the magnetic disc device.

As mentioned above, in accordance with the present invention, it ispossible to eliminate the dead space for the pivot seat, with a verysimple structure, thus realizing a small-sized magnetic disc devicewhich has practical use. This is because the distance w (FIG. 11)between the lower surface of the head arm 6e and the upper surface ofthe base 1 is considerably reduced.

A coil lead wire cable arrangement according to the present invention isdescribed hereinafter with reference to FIGS. 7 to 9.

FIG. 7 is an explanatory view of the principle of the arrangement of thepresent invention. In FIG. 7, numeral 36 designates a cable holdingmeans, which is a groove formed along a cable pass. The cable 34 isfitted into the groove.

The cable 34 is fitted and held in the groove of the holding means 36formed in the head arm 31. Therefore, it is unnecessary to use a specialinstrument for holding the cable like a clip to hold the cable, thusreducing the weight of the magnetic head structure.

An example of the cable holding arrangement according to the presentinvention is illustrated in FIGS. 8(a) and 8(b), wherein the same partsas shown in FIG. 7 are designated by the same numerals. FIG. 8(a) is aplan view of the arrangement and FIG. 8(b) is a sectional view along theline AA' of FIG. 8(a). A groove 37 is formed as a cable holding meansalong the cable pass on the head arm 31. FIG. 8(b) shows a cross sectionof the groove 37, which forms a rectangular recess for receiving thecable 34.

The cable 34 is held in this groove 37 by press fitting the cable intothe groove. An adhesive agent may be used to firmly hold the cable 34within the groove 37.

Another example of the cable holding arrangement according to thepresent invention is illustrated in FIG. 9(a), 9(b) and 9(c). A step isformed along the cable pass on the head arm 31, as shown in FIG. 9(b)which shows a cross section along the line BB' of the head arm 31 ofFIG. 9(a). As best shown in FIG. 9(b), the step has a bottom surfacewhich forms a first surface parallel to the surfaces of the magneticdisks and side surface which forms a second surface perpendicular to thefirst surface. A plurality of holder projections 38 are disposed alongthe step of the cable pass to partly form a groove-like portion, asshown in FIG. 9(c) which is a cross section along the line CC' of thehead arm 31 of FIG. 9(a). The cable 34 is held in this groove-likeportion. As a result in the present invention, the total thickness orheight of the magnetic head 5, the head arm 6e and the structure forsupporting the magnetic head can be further reduced.

As mentioned above, the magnetic head structure according to the presentinvention includes a groove as a lead wire holding means formed alongthe cable pass on the head arm, which makes it unnecessary to use aspecial cable holding instrument means, thus enabling a reduction of theweight of the magnetic head.

We claim:
 1. A half-height type magnetic disc device comprising:a base;four magnetic discs disposed one above the other on said base; five headarms rotatable about a pivot for seeking motion on both surfaces of eachmagnetic disc; eight magnetic heads each attached to an end of one ofsaid head arms through spring means and facing a surface of each disc;rotational drive means for swinging said head arms; a main printedcircuit board disposed on a rear side of said base; a cover which coversan upper surface of said base; each said magnetic head comprising aslider having a slider surface and lateral sides and a core having aheight and being disposed at one of the lateral sides of said slider forwinding a coil thereon, a lead wire of said coil being taken out from anintermediate position of said core along the height of the core; and agroove formed in a surface of each of said head arms for holding saidlead wire therein whereby said lead wire is located within the height ofthe core, the spring means and the head arm until the lead wire extendsoutside of said magnetic discs.
 2. A magnetic disc device comprising:abase; at least four magnetic discs disposed one above the other on saidbase; at least five head arms rotating about a pivot for seeking motionon both surfaces of each magnetic disc, said head arms comprising anuppermost head arm, intermediate head arms and a lowermost head arm,each of said head arms comprising a body plate of a specified thicknesspositioned parallel to the magnetic discs, the lowermost head arm beingin close proximity to the base; spring means attached to an end of eachhead arm; at least eight magnetic heads each attached to an end of oneof said head arms through the spring means and facing a surface of adisc; rotational drive means for rotating said head arms; a main printedcircuit board disposed on a rear side of said base; a cover which coversan upper surface of said base to form a casing having outer dimensionsof a half-height type magnetic disc device; the base and the lowermosthead arm defining a clearance which is less than a clearance between thehead arms;said magnetic head comprising a slider having a slider surfaceand lateral sides and a core having a height and being disposed at oneof the lateral sides of said slider for winding a coil thereon, a leadwire of said coil being taken out from an intermediate position of saidcore along the height of the core; and a groove formed in a surface ofeach of said head arms for holding said lead wire therein.
 3. A magneticdisc device according to claim 2, wherein the uppermost head arm is inclose proximity to the cover.
 4. A magnetic device according to claim 2,wherein the cover and the uppermost head arm define a clearance which isless than a clearance between the head arms.
 5. A magnetic disc deviceaccording to claim 2, wherein the thickness of the body plate of each ofthe lowermost head arm and the uppermost head arm is less than thethickness of each of the intermediate head arms.
 6. A magnetic discdevice according to claim 5, wherein the thickness of the body plate ofeach of the lowermost head arm and the uppermost arm is 2.0 millimeters.7. A magnetic disc device according to claim 6, wherein the thickness ofthe body plate of each intermediate head arm is 2.8 millimeters.
 8. Amagnetic disc device according to claim 5, wherein the thickness of thebody plate of each intermediate head arm is 2.8 millimeters.
 9. Amagnetic disc device according to claim 2, wherein each magnetic dischas a thickness of 1.27 millimeters and a gap between adjacent magneticdiscs is 4.5 millimeters.
 10. A magnetic disc device according to claim9, wherein a gap between the lower surface of the lowermost head arm andthe upper surface of the base is 0.5 millimeters.
 11. A magnetic discdevice according to claim 10, wherein the thickness of the body plate ofeach intermediate head arm is 2.8 millimeters.
 12. A magnetic discdevice according to claim 9, wherein the thickness of the body plate ofeach intermediate head arm is 2.8 millimeters.
 13. A magnetic discdevice according to claim 2, wherein the thickness of the body plate ofeach of the lowermost head arm and the uppermost arm is 2.0 millimeters.14. A magnetic disc device according to claim 2, wherein the coreincludes a portion which defines a space between the core and theslider, the space extending in a height-wise direction of the core tofacilitate winding of the coil thereon, the space extendingsubstantially from the slider surface up to the intermediate position ofthe core.
 15. A magnetic disc device according to claim 2, wherein saidrotational drive means comprises a sector secured to said head arm; acapstan disposed adjacent to said sector; and a steel belt wound aroundsaid capstan, an end of said steel belt being secured to said sector totransmit the rotational motion of said capstan to said sector.
 16. Amagnetic disc device according to claim 2, wherein said spring meanscomprises a load spring secured to an end of each head arm; a gimbalsecured to an end of said load spring; and a head supporting pieceformed by cutting an inner area of said gimbal, said supporting piecebeing bonded to a recess on an upper side of said magnetic head.
 17. Amagnetic disc device according to claim 2, wherein said head arm has acounter weight portion provided at a side opposite to said magnetic headattaching end thereof with respect to said pivot.
 18. A magnetic discdevice comprising:a housing; a printed circuit board disposed on a sideof said housing, a height of the magnetic disc device, including saidhousing and said printed circuit board, being of a height of ahalf-height type of a magnetic disc device; at least four magnetic discsdisposed in said housing; at least eight magnetic heads each facing asurface of a disc, each said magnetic head comprising a slider having aslider surface and having a height in a direction perpendicular to theslider surface; at least five head arms rotatable about a pivot forseeking motion on both surfaces of each magnetic disc, each of said headarms being moved over the respective surfaces of said magnetic discsduring operation of the disc device, each of said head arms having afirst surface parallel to the surfaces of said magnetic discs and asecond surface perpendicular to the first surface; rotational drivemeans for swinging said head arms; a support structure supporting eachsaid magnetic head, said support structure including a spring member forattaching said magnetic head to an end of one of said head arms; a coilwinding fixed to each said magnetic head, said coil winding beinglocated within the height of said magnetic head, the height of saidmagnetic head being in a direction perpendicular to the surfaces of saidmagnetic discs; a lead wire connected to said coil winding tocommunicate a signal between said printed circuit board and said coilwinding; and means for holding said lead wire to the second surface ofsaid head arm by press-fitting, said lead wire being located within atotal thickness of said magnetic head, said spring member, and said headarm, and along said head arm until said lead wire extends to outside ofsaid magnetic disc.
 19. A magnetic disc device according to claim 18,wherein said slider of each magnetic head has lateral sides; saidmagnetic head further comprises a core having a height in a directionperpendicular to the slider surface and being disposed at one of thelateral sides of the slider for winding a coil winding thereon; andwherein said lead wire is taken out from an intermediate portion of thecore along the height of the core.
 20. A magnetic disc devicecomprising:a housing: a printed circuit board disposed on a side of saidhousing, a height of the magnetic disc device, including said housingand said printed circuit board, being of a height of a half-height typeof a magnetic disc device; at least four magnetic discs disposed in saidhousing; at least eight magnetic heads each facing a surface of a disc,each said magnetic head comprising a slider having a slider surface andhaving a height in a direction perpendicular to the slider surface; atleast five head arms rotatable about a pivot for seeking motion on bothsurfaces of each magnetic disc; rotational drive means for swinging saidhead arms; a support structure supporting each said magnetic head, saidsupport structure including a spring member for attaching said magnetichead to an end of one of said head arms; a coil winding fixed to eachsaid magnetic head, said coil winding being located within the height ofsaid magnetic head; a lead wire connected to said coil winding tocommunicate a signal between said printed circuit board and said coilwinding, said lead wire being located within a total thickness of saidmagnetic head, said spring member, and said head arm until said leadwire extends to outside of said magnetic disc, and wherein each of saidhead arms has a groove on a surface thereof and said lead wire ispositioned in said groove.
 21. A magnetic disc device comprising:ahousing; a printed circuit board disposed on a side of said housing, aheight of the magnetic disc device, including said housing and saidprinted circuit board, being of a height of a half-height type of amagnetic disc device; at least four magnetic discs disposed in saidhousing; at least eight magnetic heads each facing a surface of a disc,each said magnetic head comprising a slider having a slider surface andhaving a height in a direction perpendicular to the slider surface; atleast five head arms rotatable about a pivot for seeking motion on bothsurfaces of each magnetic disc; rotational drive means for swinging saidhead arms; a support structure supporting each said magnetic head, saidsupport structure including a spring member for attaching said magnetichead to an end of one of said head arms; a coil winding fixed to eachsaid magnetic head, said coil winding being located within the height ofsaid magnetic head; a lead wire connected to said coil winding tocommunicate a signal between said printed circuit board and said coilwinding, said lead wire being located within a total thickness of saidmagnetic head, said spring member, and said head arm until said leadwire extends to outside of said magnetic disc; and wherein each of saidhead arms has a groove on a surface thereof; said slider of eachmagnetic head has lateral sides; said magnetic head further comprises acore having a height in a direction perpendicular to the slider surfaceand being disposed at one of the lateral sides of the slider for windinga coil winding thereon; and wherein said lead wire is positioned in thegroove of said head arm, and is taken out from an intermediate portionof the core along the height of the core.
 22. A magnetic disc devicecomprising:a housing; a printed circuit board disposed on a side of saidhousing, a height of the magnetic disc device, including said housingand said printed circuit board, being of a height of a half-height typeof a magnetic disc device; at least four magnetic discs disposed in saidhousing; at least eight magnetic heads each facing a surface of a disc,each said magnetic head comprising a slider having a slider surface andhaving a height in a direction perpendicular to the slider surface; atleast five head arms rotatable about a pivot for seeking motion on bothsurfaces of each magnetic disc, each of said head arms being moved overthe respective surfaces of said magnetic discs during operation of thedisc device, each of said head arms having a first surface parallel tothe surfaces of said magnetic discs, and a second surface perpendicularto the first surface; rotational drive means for swinging said headarms; a support structure supporting each said magnetic head, saidsupport structure including a spring member for attaching said magnetichead to an end of one of said head arms; a coil winding fixed to eachsaid magnetic head, said coil winding being located within the height ofsaid magnetic head, the height of said magnetic head being in adirection perpendicular to the surfaces of said magnetic discs; a leadwire connected to said coil winding to communicate a signal between saidprinted circuit board and said coil winding, said lead wire beinglocated within a total thickness of said magnetic head, said springmember, and said head arm until said lead wire extends to outside ofsaid magnetic disc; and means for holding said lead wire to the secondsurface of said head arm by press fitting along said head arm and withina total thickness of said magnetic head, said spring member, and saidhead arm until said lead wire extends to outside of said magnetic disc.23. A magnetic disc device comprising:a housing; a printed circuit boarddisposed on a side of said housing, a height of the magnetic discdevice, including said housing and said printed circuit board, being ofa height of a half-height type of a magnetic disc device; at least fourmagnetic discs disposed in said housing; at least eight magnetic headseach facing a surface of a disc, each said magnetic head comprising aslider having a slider surface and having a height in a directionperpendicular to the slider surface; at least five head arms rotatableabout a pivot for seeking motion on both surfaces of each magnetic disc,each of said head arms being moved over the respective surfaces of saidmagnetic discs during operation of the disc device; rotational drivemeans for swinging said head arms; a support structure supporting eachsaid magnetic head, said support structure including a spring member forattaching said magnetic head to an end of one of said head arms; a coilwinding fixed to each said magnetic head, said coil winding beinglocated within the height of said magnetic head, the height of saidmagnetic head being in a direction perpendicular to the surfaces of saidmagnetic discs; a lead wire connection to said coil winding tocommunicate a signal between said printed circuit board and said coilwinding, said lead wire being located within a total thickness of saidmagnetic head, said spring member, and said head arm until said leadwire extends to outside of said magnetic disc; and means for holdingsaid lead wire along said head arm and within a total thickness of saidmagnetic head, said spring members, and said head arm, until said leadwire extends to outside of said magnetic disc, said means for holdingsaid lead wire comprising a groove provided in said head arm.